Analysis of production processes of lower trophic levels in upwelling ecosystem

研究的重点是低营养级生物，特别是浮游植物和浮游动物，对区域涌升的特定水体中环境的快速和剧烈变化的传播反应，这些涌升具有小面积和短时间尺度，例如海面上几公里，时间尺度为几天至一周。建立了地面监测系统和OCTOPUS实验装置，并引入了空间遥感技术和XBT技术。由于区域上升流的研究不可避免地要进行地球物理处理，因此，在日本科学促进会和美国国家科学基金会的“日美合作科学计划”的资助下，邀请了美国地球物理学家参加。在日本伊豆群岛进行了田间试验。东京大学海洋研究所的V. Tansei-Maru和海洋研究中心的“Tsukuba” ...更多信息 f筑波大学。主要的注意力被给予一个给定的涌上水团的检测，并遵循各种生物过程的时间变化和涌上水团。获得的结果如下。研究区普遍存在30 ~ 100 m深的水团涌至地表。浮游植物繁殖在上升流后的几天内被激活，浮游植物生物量随时间呈指数增长。所有浮游植物类群都受到了生长刺激，其中硅藻的几种受到的刺激尤为显著。新涌升水体中浮游植物光合产物富含蛋白质，导致浮游植物种群规模扩大。另一方面，在较老的涌升水团中，光合产物主要由糖等能源组成，这导致维持现有种群而不是规模扩张。在浮游动物种群中也观察到类似的增长刺激，其中雌性浮游植物生物量的增加，广泛增加产卵率。少

Research has been focussed on the propagation responses of lower trophic level organisms, particularly phyto- and zoo-plankton, to rapid and drastic changes in the environment in a given water mass of regional upwelling having small areal and short temporal scales such as a few kilometers at the sea surface and a few days to one week of temporal scale. Experimental setups of a surface monitoring system and OCTOPUS have been developed, and remote sensing technique from space and XBT were also introduced for the research. Since geophysical treatment was unavoidable for the research of regional upwelling, participation of US geophysicists were invited by the financial supports of "The Japan-US Cooperative Science Program" of the Japan Society for the Promotion of Science and the National Science Foundation in USA. Field experiments were carried out in the area of Izu Islands using R. V. Tansei-Maru of Ocean Research Institute, University of Tokyo, and "Tsukuba" of Marine Research Center o … More f University of Tsukuba. Major attention was given to the detection of a given upwelled water mass, and to follow the temporal changes of various biological processes in and out of the upwelled water mass. Results obtained are as follows. Water mass of 30 to 100m in depth was generally upwelled to the surface in the study area. Phytoplankton propagation was activated within a few days after upwelling, and phytoplankton biomass increased exponentially with time. Growth stimulation occurred in all the groups of phytoplankton, and a few species of diatom were particularly enhanced greatly. Photosynthetic products of phytoplankton in newly upwelled water mass was rich in proteins, which resulted in an enlargement of phytoplankton population size. In older upwelled water mass, on the other hand, photosynthetic products were mainly composed of energy sources such as sugars, which resulted in maintaining the existing population rather than size expansion. Similar growth stimulation in upwelled water mass also observed in zooplankton population in which females extensively increased egg production rate with the increase of phytoplankton biomass. Less